1. What is a PSI GPM Flow Rate Calculator?

Definition: This calculator determines the flow rate in gallons per minute (GPM) through a pipe based on pressure difference (PSI), fluid density, and pipe diameter.

Purpose: It helps engineers, plumbers, and fluid system designers calculate flow rates for various applications like water supply, irrigation, and industrial processes.

2. How Does the Calculator Work?

The calculator uses two fundamental formulas:

Where:

• \( V \) — Fluid velocity (feet per second)
• \( P_1 \) — Upstream pressure (psi)
• \( P_2 \) — Downstream pressure (psi)
• \( \rho \) — Fluid density (pounds per cubic foot)
• \( Q \) — Flow rate (gallons per minute)
• \( A \) — Cross-sectional area of pipe (square feet)

Explanation: The first formula calculates velocity from pressure difference, then the second converts velocity to flow rate using pipe area.

3. Importance of Flow Rate Calculation

Details: Accurate flow rate calculations ensure proper system design, prevent pipe damage from excessive velocity, and help select appropriate pump sizes.

4. Using the Calculator

Tips: Enter the pressure difference (P₁ - P₂), fluid density (default 62.4 lb/ft³ for water), and pipe diameter in inches. All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What's the 144 factor in the formula?
A: This converts psi (lb/in²) to lb/ft² (1 ft² = 144 in²).

Q2: Why 448.83 in the flow rate formula?
A: This converts ft³/s to GPM (1 ft³/s = 448.83 GPM).

Q3: What's a typical water density value?
A: Pure water at 60°F is 62.4 lb/ft³. Adjust for temperature or other fluids.

Q4: Does this account for friction losses?
A: No, this is ideal flow. For long pipes, consider additional calculations for friction losses.

Q5: What's the maximum velocity recommended?
A: Typically 5-8 ft/s for water to prevent erosion and noise.